I think management uses salary to keep people at the company rather than to motivate them to be more productive. And if you're a manager, you want to keep people who have a lot of knowledge of the code that isn't either well captured in automated tests/documentation or easily figured out from looking at their code, ie. crappy programmers. Good programmers are able to write simpler, better tested and documented code so it's less work for others to maintain it if they leave. Paradoxically, if you're working at a 9-5 programming job, you have more incentive to be mediocre than great.